Journal of Vector Ecology 251

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1 Vol. 30, no. 2 Journal of Vector Ecology 251 Bionomics and distribution of species of Hystrichopsylla in Arizona and New Mexico, with a description of Hystrichopsylla dippiei obliqua, n. ssp. (Siphonaptera: Hystrichopsyllidae) Michael W. Hastriter 1 and Glenn E. Haas 2 1 Monte L. Bean Life Science Museum, Brigham Young University, 290 MLBM, P.O. Box 20200, Provo, UT , U.S.A California Avenue, PMB O7, Boulder City, NV 89005, U.S.A. Received 3 February 2005; Accepted 12 April 2005 ABSTRACT: More than 450 specimens of Hystrichopsylla were collected from nests and hosts of species of Microtus, Neotoma, Tamiasciurus, and Peromyscus in Arizona and New Mexico from A new subspecies, Hystrichopsylla dippiei obliqua, is described and a map illustrating the distribution of the three taxa (Hystrichopsylla dippiei truncata Holland, H. d. obliqua, and H. occidentalis sylvaticus Campos and Stark) occurring in Arizona and New Mexico is provided. Hystrichopsylla. o. sylvaticus is reported in New Mexico for the first time and H. d. truncata is a new record in Rio Aribba County, NM. Relationships of Mexican species are also discussed. These large fleas are seldom collected from the fur of their mammalian hosts (usually singly) but are prevalent in moist nests. The maximum number of the new subspecies collected from a single nest was 54. Dry nests, particularly those that are not subterranean or otherwise protected from desiccation, do not support development of Hystrichopsylla fleas. Minimum elevation at which H. dippiei ssp. is found in Arizona and New Mexico appears to be about 2,100 m. Journal of Vector Ecology 30 (2): Keyword Index: Hystrichopsylla dippiei, Hystrichopsylla occidentalis, Siphonaptera, flea. INTRODUCTION Lewis and Lewis (1994) discuss the two nominate species, H. dippiei dippiei Rothschild, 1902 and H. occidentalis occidentalis Holland, 1949, and their subspecific taxa in the western United States. Specimens of H. dippiei ssp. were recorded from New Mexico by Traub and Hoff (1951) and Ford et al. (2004) and from Arizona by Beer et al. (1959), Holland (1957), and Hubbard (1947). A male reported from Arizona by the latter author was further identified by Hopkins and Rothschild (1962) as H. dippiei truncata Holland, Holland (1957) and Haas et al. (1973) reported H. d. truncata from New Mexico, and Campos and Stark (1979) reported H. o. sylvaticus Campos and Stark, 1979 from Arizona. Fagerlund et al. (2001) reported H. o. linsdalei Holland, 1957 from New Mexico, which is extralimital and likely represented H. o. sylvaticus. The present study is one of several (Kucera and Haas 1992, Haas and Wilson 1998, Lewis and Haas 2001, Haas and Kucera 2004, and Haas et al. 2004) related to an expansion within the Southwest of an earlier ( ) survey of fleas concentrated in and close to the Jemez Mountains, NM (Haas et al. 1972, 1973, Haas 1972, 1973, Méndez and Haas 1972, 1973). Lewis and Eckerlin (2004) described a new species from Guatemala and provided a key for the known Mexican and Central American species of Hystrichopsylla. During the 1980s and 1990s, the emphasis shifted from trapping rodent hosts for their fleas to extracting and rearing fleas from the nests of chipmunks [Tamias (Neotamias) spp.], red squirrels [Tamiasciurus hudsonicus Erxleben)], mice (Peromyscus spp.), woodrats (Neotoma spp.), and voles (Microtus spp.). The data from these extractions and rearings are reported in this paper. Some findings are presented for hystrichopsyllid material collected from host animals, and relevant discussions of Mexican species are included. MATERIALS AND METHODS The junior author collected most of the fleas in this study from Arizona and New Mexico during the months of May through November Most recent collections (2002 and 2004) were provided by James R. Kucera. Specimens from collections of other institutions were also examined and included herein. Table 1 illustrates the number of nests examined and the number of each sex recovered from the specified host s nest. Although more nests were collected, the rodent species was uncertain. Such nests and the numbers of fleas recovered are not included in Table 1, but specimens were examined. Figure 1 provides distribution records for H. dippiei ssp. in Arizona and New Mexico and H. o. sylvaticus is included to illustrate the spatial relationships of all three taxa. Most of our flea specimens came from mixed coniferous montane forests and meadows therein. The dominant associated members of these plant communities occurring in our study areas are described in the biotic community classification system of Brown et al. (1998). Four of these areas described by Brown et al. characterize the habitats from which collections were obtained. They are described below and may be associated with each collection made by either

2 252 Journal of Vector Ecology December 2005 the junior author or James R. Kucera. These (habitats 1-4 below) are annotated within parentheses immediately after the collector in the Materials Examined sections, i.e. T. hudsonicus nest, 30 September 1998, G.E. Haas (1), 4 males, 14 female, (RN-143);. Habitat 1: Rocky Mountain and Great Basin subalpine conifer forest (Brown et al., plate 13), with dominant stands of Englemann spruce (Picea engelmanni Parry) and the alpine fir [Abies lasiocarpa (Hooker)]. Higher north facing slopes and narrow east-west facing canyons were particularly important habitats for red squirrels. Non-coniferous trees frequently used by rodents for nesting included the quaking aspen (Populus tremuloides Michaux). Habitat 2: Rocky Mountain alpine and subalpine grassland (plate 53), with expanses of Thurber fescue (Festuca thurberi Vasey) and other forbs. Such habitats provided ample niches for Microtus montanus (Peale). Habitat 3: Rocky Mountain montane grassland and its conifer associations (plate 59), with meadows of herbaceous forbes were favored habitats for the long-tailed vole [Microtus longicaudus (Merriam)]. Associated communities of Douglas fir [Pseudotsuga menziesii (Mirbel)] and white fir [Abies concolor (Gordon & Glendinning)] generally surrounded these meadows and were commonly associated (unlisted by Brown et al.) with the Blue spruce (Picea pungens Engelmann), a favorite of the red squirrel in New Mexico (Findley et al. 1975). The Limber pine (Pinus flexilis James), although present, was less common. Ponderosa pine (Pinus ponderosa Douglas) dominated in the driest sites having prolonged exposure to the sun (see below). Habitat 4: Rocky Mountain montane conifer forest (plate 22), which often has nearly pure stands of ponderosa pine/ yellow pine (P. ponderosa). These sites are drier and at lower elevations than the three previous communities and provide nesting habitats for Abert s squirrel (Sciurus aberti Woodhouse) and the Mexican vole [Microtus mexicanus (Saussure)]. A description of this biotic community is included to illustrate a habitat with favorable hosts on which few specimens of Hystrichopsylla spp. were collected. Some common non-conifer associates of ponderosa pines listed by Brown et al. (1998) included the Gambel oak (Quercus gambelii Nuttall) found in our northern study areas, Arizona white oak (Quercus arizona Sarg.) in the southern study areas, and the widespread quaking aspen. Little (1950) tabulated the annual rainfall for 12 vegetation types. Two of these include Douglas fir-mixed conifer-aspen forests (maximum of mm) and spruce-fir forests (maximum of mm). In general, our habitats 1-3 above receive an annual rainfall in excess of 600 mm (mostly as winter snows). Habitats at lower elevations that do not support these plant communities (habitat 4) receive less annual moisture and are not suitable for species of Hystrichopsylla. Habitats of the red squirrel and other selected rodents were searched for likely nest sites. These sites were scrutinized for rodent signs, e.g., middens, droppings, and runways. Calls and sightings confirmed the presence of certain species. Helpful guides to distributions, locality records, food habits, behavior, and nest ecology included the monographs of Bailey (1932), Hoffmeister (1956, 1986), Findley (1987), Findley et al. (1975), and Brown (1984). Each nest was removed as intact as possible from its site, inserted into an empty plastic bag, labeled, sealed, and taken to a place where it could be examined immediately or stored temporarily in a sheltered place out of direct sunlight. Each was meticulously examined for adult fleas and larvae over a light-colored pan. Adults and some of the larvae were preserved in ethanol, while most of the larvae were returned to the same nesting material (coarse material discarded) for rearing additional adults. These rearing bags were left open and inserted into larger bags containing moistened paper towels. The outer bags were sealed and stored in a dark place at room temperature (18-24 C). The inner bags were re-examined for newly-emerged adult fleas at 1-4 week intervals. Teneral fleas were captured and moist paper towels were renewed periodically until no more fleas appeared (usually within 2 months). Trapped animals were obtained using Sherman aluminum collapsible traps baited with oatmeal and snap traps baited with peanut butter. Trapping was a minor part of this study (only 12 hosts opposed to 85 nests) and no trapping was done in New Mexico. It was necessary to trap in Arizona because T. hudsonicus does not occur in the Chiricahua Mountains, Cochise County, AZ (Hoffmeister 1986) and nests of other rodents could not be found at high elevations. The endangered status of the endemic Mt. Graham red squirrel [T. h. grahamensis (J.A. Allen)] within the Pinaleno Mountains, Graham County, AZ precluded trapping or nest collections (see Istock and Hoffman 1995). However, 35 fleainfested nests of the long-tailed vole (M. longicaudus) were collected in Arizona, as the vole and its nests were abundant. Each animal was brushed over a light-colored pan and fleas were preserved in 70% ethanol. Collections included numerous fleas from lower elevations in the Sonoran Desert to higher elevations of the alpine valleys and slopes. Although many species of fleas were obtained, this report addresses only species of Hystrichopsylla. They were found only at elevations above 2,164 m. Voles were predominantly found in wet areas along streams and in meadows, woodrats in rocky ecotones at higher elevations, Abert s squirrels in ponderosa forests (lower elevations), and red squirrels in mixed coniferous forests, particularly densely wooded north facing slopes and shaded ravines. In addition to specimens collected during this study, numerous specimens were examined from different institutions. A listing of institutions or individual flea collections designating repository of specimens with associated acronyms follow. Those parenthetical acronyms that are deposited in the respective institution or collection are listed after those specimens in the sections entitled Materials Examined.

3 Vol. 30, no. 2 Journal of Vector Ecology 253 BYU Brigham Young University Flea Collection, Monte L. Bean Life Science Museum, Provo, UT; CMNH Section of Invertebrate Zoology, Carnegie Museum of Natural History, Pittsburgh, PA; CNC Canadian National Collections of Insects, Arachnids and Nematodes, Ottawa, Ontario, Canada; GEH Personal collection of Glenn E. Haas, Boulder City, NV; JRK Personal collection of James R. Kucera, Salt Lake City, UT; MWH Personal collection of Michael W. Hastriter, Monte L. Bean Life Science Museum, Provo, UT; USNM Division of Systematic Biology-Entomology, National Museum of Natural History, Smithsonian Institution, Washington, D.C.; and UNM Museum of Southwestern Biology, University of New Mexico, Albuquerque, NM. Adults were mounted using conventional flea mounting techniques. Because of their large size, it was often necessary to shim the cover glass with glass shards to hold it parallel to the slide. Dissections of males were ultimately necessary for more detailed studies. Since all male specimens were mounted years before these final studies, slide mounted specimens were selected and placed in petri dishes in xylene until the Canada balsam media was dissolved sufficiently to free the specimens (usually overnight). Dissections were conducted in xylene by removing the right terga and sterna IX (t. IX, st. IX) and the aedeagus with minuten nadeln mounted at the tip of applicator sticks. Because of their extremely small size, these anatomical parts were picked up under one dissecting scope with a minute spatula and transferred into a small drop of Canada balsam on a microscope slide under an adjacent dissecting microscope. The remaining whole flea was mounted adjacent to the dissected parts under a second coverslip to facilitate associated morphology. An Olympus BX61compound microscope, Olympus SZX-12 stereo microscope, Olympus CV12 digital camera, Olympus Microsuite B3SV program, and Adobe Photoshop 7.0 were used to prepare images. Mammal taxa and their synonymies follow those of Wilson and Reeder (1993) and are specified in the text where synonymies occur. RESULTS AND DISCUSSION Hystrichopsylla dippiei obliqua new subspecies, Hastriter and Haas Figure 1, Figure 2A-C, Figures 3A-G, Table 1 Type Material. -United States. New Mexico: Catron County. Mogollon Mountains: Snow Canyon, 4.3 km NW Snow Lake Dam, 3.3 km W up canyon from tank, 2,347 m, ( "N "W), T. hudsonicus nest, 30 September 1998, G.E. Haas (3), male holotype, female allotype, 4 males, 14 females (RN-143); same data except 4 km NW Snow Lake Dam, 2,341 m, ( "N "W), 11 June 1998, 1 female (RN-139); S rim Snow Canyon, 4 km NW Snow Lake Dam, 2,408 m, ( "N "W), Neotoma mexicana Baird, 28 September 1996, G.E. Haas (3), 1 male (WN-46); 21.3 km E Mogollon, Gilita Creek, 2,393 m, ( "N "W), N. mexicana + Peromyscus maniculatus (Wagner) nest, 8 September 1995, G.E. Haas (3), 1 male (WN-44 + P-14); 18.5 km E Mogollon, Willow Creek, 2,444m ( "N "W), N. mexicana nest + P. maniculatus nest, 23 September 1991, G.E. Haas (3), 1 female (WN-35 + P-10); 19.3 km ENE Mogollon, Quaking Aspen Creek, Bear Wallow Lookout Road, FR 119, 2,524 m, ( "N "W), T. hudsonicus nest, 1 October 1998, G.E. Haas (3), 1 female (RN-144); 16.9 km NE Mogollon, SE slope of Corner Mountain, Bill Lewis Cienega, 2,719 m, ( "N "W), T. hudsonicus nest, 29 September 1996, G.E. Haas (3), 1 female (RN-134); Tularosa Mountains: 10.1 km SE Apache Creek, Five Springs Canyon between Springs and head of canyon, 2,621 m, (33 15 N "W), N. mexicana nest, 3 October 1999, G.E. Haas (3), 2 females (WN- 50/51); 9.1 km SE Apache Creek, Five Springs Canyon, 0.3 km W Five Springs tank, 2,195 m, (33 15 N "W), T. hudsonicus nest, 27 September 1996, G.E. Haas (3), 1 male, 3 females (RN-132). Grant County. Mimbres Mountains: 16.6 km NE San Lorenzo post office, Iron Creek Canyon, Iron Creek Campground, 2,195 m, ( "N "W), M. mexicanus, nest, 9 September 1992, G.E. Haas, 1 male, 1 female (V-24). Socorro County. San Mateo Mountains: 1.7 km, WNW Mt. Withington, Bear Trap Canyon, 2,658 m, ( "N "W), T. hudsonicus nest, 22 August 1993, G.E. Haas (1), 4 males, 1 female (RN-98); same data, 2 males (14 males, 12 females in alcohol)(rn- 97). Torrance County. Manzano Mountains: 8.1 km SW Manzano, Ox Canyon, Forest Trail 190, 2,499 m, ( "N "W), T. hudsonicus nest, 9 August 1991, G.E. Haas (3), 13 males, 11 females (RN-70) (GEH). The holotype, allotype and six paratypes (3 males, 3 females) are deposited in the National Museum of Natural History, Washington, D.C., five paratypes (2 males, 3 females) in the Carnegie Museum of Natural History, Pittsburgh, PA, four paratypes (2 males, 2 females) in the junior author s collection, 6 paratypes (3 males, 3 females) in the senior author s collection and the remaining paratypes in the Brigham Young University collection, Monte L. Bean Life Science Museum, Provo, UT. Other material examined: Mexico. Nuevo León. Sierra Madre Oriental Range: Cerro Potosi, 14 km N Galeana, 2,896 m, (~24 57 N W), Microtus sp., 18 May 1963, A.D. Stock and J.H. Shaw, 1 male; 18 km N Galeana, 2,896 m, (~24 59 N W), Peromyscus melanotus J.A. Allen and Chapman, 1897, February 1963, A.D. Stock and J.H. Shaw, 2 females; El Potosi, 2,896 m, (~24 51 N W), Microtus sp., 21 May 1963, A.D. Stock and J.H. Shaw, 1 male, 3 females (CMNH). United States. Arizona: Graham County. Pinaleno Mountains: 4 km W Mt. Graham, 0.4 km S USFS Columbine Work Center, 2,877-2,894 m, (32 42 N "W), M. longicaudus nests (5), 8-11 September 1987, G.E. Haas (3), 11 males, 8 females; same data except 2,918 m, M. longicaudus + N. mexicana nests, 21 May 1990, 1 male, 2 females; M. longicaudus, 17 May 1990, 1 male; 2,915 m, N. mexicana nest, 18 May 1990, 2 males, 5 females; 1.1 km NW Heliograph Peak, Shannon Park, near Heliograph Peak Road, 2,774 m, ( "N "W), M. longicaudus

4 254 Journal of Vector Ecology December 2005 nest, 18 November 1989, G.E. Haas (3), 1 male; same data except N. mexicana nest, 19 November 1989, 16 males; same data except 20 October 1991, 4 males, 3 females; same data except 2,714 m, 19 October 1991, 3 males, 17 females; (GEH); 0.3 km S Heliograph Peak, N. mexicana, 9 August 1951, R.G. van Gelder, 1 female (CMNH); 9 km W Mt. Graham, Riggs Flat near E shore of Riggs Lake, 2,652 m ( "N "W), M. longicaudus, 15 May 1990, G.E. Haas (3), 1 male 2 females; 3.6 km WSW Mt Graham, 1.2 km SSE Columbine Work Center, 2,896 m ( "N "W), M. longicaudus nest, 17 May 1990, G.E. Haas (3), 8 males, 3 females; 6.4 km WNW Mt. Graham, Chesley Flat, 2,816 m, ( "N "W), M. longicaudus nests (2), 12 September 1987, G.E. Haas (3), 13 males 6 females, (GEH). New Mexico: Catron County. Mogollon Mountains: Snow Canyon, 4.3 km NW Snow Lake Dam, 2,344 m, ( "N "W), T. hudsonicus nest, 11 June 1998, G.E. Haas (3), 1 female (GEH); and 32 km NE Mogollon, 2,409 m, (~33 35 N W), Microtus sp., 7 November 1950, 1 female (CNC). Lincoln County. Sacramento Mountains: 11.3 km N Ruidoso, Sierra Blanca east foothills, (~33 25 N W), Microtus pennsylvanicus (Ord), 4 December 1951, 1 male; 9.7 km N Ruidoso, Sierra Blanca east foothills, (~33 25 N W), Neotoma albigula Hartley, 4 December 1951, 1 male (USNM). Socorro County. Magdalena Mountains: near S Baldy Peak at Langmuir Labs, host unlisted, 12 September 1990, 1 female (UNM). Diagnosis: Material from Arizona and New Mexico is represented by taxa belonging to both the H. dippiei and the H. occidentalis complexes. These may be distinguished by the number of spines in the genal ctenidium. Hystrichopsylla dippiei ssp. usually has six spines per side in the genal ctenidium (infrequently seven) (Figures 2A-B), while H. occidentalis ssp. usually have eight or more on each side. The H. dippiei subspecies include H. d. dippiei Rothschild, 1902 (north central U.S. and Alberta, Canada), H. d. neotomae Holland, 1957 (coastal central California), H. d. spinata Holland, 1949 (Vancouver, British Columbia, Canada through Alaska s southern archipelago), H. d. truncata (east of the Cascades and the Sierras from British Columbia, Canada to Arizona and New Mexico), and H. d. obliqua (Arizona, New Mexico, and Mexico). Males are separable from nominate subspecies by the presence of tubercles on the dorsal angle of st. IX. The oblique angle of the apex of the distal arm of the ninth sternum (DA9) is distinctive in the new subspecies opposed to a more truncate apex in H. d. spinata and H. d. truncata, and less oblique in H. d. neotomae. The latter species also has prominent tubercles versus the flattened scale-like tubercles found in H. d. obliqua. The new subspecies usually possess one or two small spiniform setae between the proximal and penultimate larger spiniforms along the caudal margin of the st. IX (Figures 3D-E). This character occurs in other taxa as well; however, 76/78 males of H. d. obliqua possess the small spiniform between the proximal and penultimate larger spiniforms versus only 7/42 males of H. d. truncata. The anterior margin of st. IX is essentially straight in the new subspecies, whereas it is strongly reflected forward in other H. dippiei ssp. (Figures 3B, 3D-L). This forward inflection creates a concavity along the anterior margins. Females in the absence of males can not be distinguished for certain from H. d. truncata in Arizona and New Mexico; however, the margin of the t. VIII tends to have a marked concavity or flattened region opposite the dorsal most marginal seta, whereas it is rounded in H. d. truncata (Figure 3C). Females of the new subspecies also have a greater number of marginal spinelets on t. II (Figure 2B) than H. d. truncata (range: 6-12, mean: 8.3 (n=38) vs. range: 4-8, mean: 6 (n=38)]. In addition to H. d. obliqua, Mexico taxa possessing six genal ctenidia include H. orophila Barerra, 1952 (females unknown) and H. kris Traub and Johnson, 1952 (males unknown). Separable from the female of H. kris by its much smaller size and the abdominal spiracle VIII extends to the margin of tergum IX and from the male of H. orophila by the broadly rounded apical margin of the basimere, rounded apex on securifer of Ford s sclerite, and broader distal arm of sternum IX. Description: Reference to the numbers of setae, spinelets, spiniforms, etc. refer to one side only. General anatomy of females may be assumed to be the same as males unless otherwise specified. Head (Figures 2A-B). Preantennal area with an ocular row of three setae, central single long seta at margin of antennal fossa, frontal row of six slender setae, with numerous scattered small setae all posterior to frontal row. Submarginal area of frons (anterior to frontal row) finely punctate with two placoids near margin. Well-developed tentorial arch anterior to eye; area communis large. Small pigmented eye with ventral sinus. Area between frontal tubercle and oral angle with thick sclerotization. Falx of female complete; much longer than male. Post-antennal area with three rows of setae; ventral two setae in posterior row much longer than others. Male with occipital groove, both sexes with two placoids (anterior placoid of male located in antennal groove). Group of setae dorsal to antennal fossa. Antennal scape with basal patch of small setae (seven to ten), apex with three to four long setae; pedicel with fringe of short setae extending ~1/4 length of clavus (slightly longer in female). Male clavus extends onto prosternum. Genal ctenidium usually with six pigmented spines (rarely seven). Ventral margin of genal lobe extending ventrad over basal coxa in female; not expanded in male. Maxilla acutely pointed, labial palpus of five segments not reaching apex of coxa. Thorax (Figures 2A-B). Pronotal ctenidium of spines; two rows of setae. Prosternum and proepimeron divided. Mesonotum with main row of setae, five anterior rows. Mesopleural rod bifurcate dorsally; mesopleuron with numerous scattered small setae anteriorly, larger setae caudally. Metanotum with main row, three anterior rows. Lateral pleural area divided by sclerotized ridge, two setae in each area. Metepisternum with single large seta, metasternum without setae. Metepimeron with vertical line of six setae in main row; ten scattered setae anteriorly in male, 15 in female. Spiracular fossa long and pointed. Legs. In general, legs very setiferous. Proximal ventral margin of each coxa with two large setae. Two femoral pit setae each leg. Setae guarding femoral-tibial joint: foreleg with large lateral, small medial

5 Vol. 30, no. 2 Journal of Vector Ecology 255 setae; mid- and hind leg, each with small lateral, large medial setae. Dorsal margin of tibia with eight notches in fore leg; mid- and hind legs each with nine notches. Five lateral plantar bristles on each distotarsomere. Unmodified Abdominal Segments (Figures 2A-B). Marginal spinelets on t. II-IV of female (average: seven, four and two, respectively in Pinaleno specimens, n=30; eight, four, and three in other areas, n=38) and male t. II-IV (average: seven, four, and three, respectively in Pinaleno specimens, n=40; eight, four, and three in other areas, n=24). Three specimens in the Pinalenos had a single spinelet on t. V. Tergites each with three rows of setae, main row in females strongly curved cephalad on t. IV-VI. Spiracular fossae round; rows of setae extend far below level of spiracles, especially in females. Three antesensilial bristles, middle longest, mesal shortest. Sternum II with single seta per side with several smaller setae cephalad; female with expansion or lobe on ventro-anterior angle of st. II. Male st. III with four setae in main row, st. IV-VI each with three, st. VII each with three-four, patch of smaller setae anterior to main rows. Female same except five-six setae in main row st. III-VI; with many smaller setae in front of main rows. Modified Abdominal Segments, male. Tergum VIII reduced; patch of five to seven setae dorsad to terminal spiracle. Basimere and telomere as in Figure 3B. Patch of setae along caudal base of manubrium well below acetabulum. Acetabular bristles missing. Sternum VIII with fringe of many long, posteriorly directed, slender setae on posterior half; anterior portion with many very short setae directed towards base of sternite. Shape of apex subject to orientation. Sternum IX adorned with six-seven pairs of spiniform setae along caudal margin. Smaller supernumerary setae are interspersed particularly between the ventral most pair and the penultimate pair. Small patch of fine setae below spiniforms; upper third of anterior margin st. IX with seven-eight caudally directed fine setae. Diagonal lateral line from base to apex; generally very straight in this species (Figures 3B, D-G). Numerous scale-like tubercles on the dorsal swelling where distal and proximal arms merge. Apodemal rod of st. IX absent (Figure 3B). Aedeagus. Aedeagus as in Figure 2C. Ford s sclerite (F.sc) well developed. Median dorsal lobe surrounding F.sc as extended hyaline margin. Median dorsal lobe flanked by accessory lateral lobes that extend to middle of aedeagal apodeme. Lateral lobes enveloping sclerotized inner tube (s.i.t.); dorsal armature (d.ar.) attaching s.i.t. to F.sc. by a hyaline membrane. Aedeagal pouch (ae.p.) thin, membranous on distal portion; well-sclerotized caudally. Penis rods extend just beyond apex of aedeagal apodeme. Elliptical patch of minute setae beneath aedeagal pouch on ventro-lateral surface near proximal portion of virga ventralis (Figure 2C). Modified Abdominal Segments, female (Figure 3C). Sensilium with heavily sclerotized posterior margin. Sternum VII emarginate with ventral lobe; numerous small setae anterior to main row of eight long setae. Sternum VIII extends dorsad to terminal spiracle; bearing many setae, five-six marginal. Margin of st. VIII variable; most specimens with flattened, or concave margin opposite uppermost long marginal seta. Group of sixeight variable sized setae on mesal surface of st. VIII. Side of anal stylet parallel, three times as long as wide; single long apical bristle with minute seta on dorsum at base of bristle. Ventral anal lobe setiferous with two long undulating apical setae. Two spermathecae, bulga slightly broader at base than near hilla (Figure 3C). Bursa copulatrix membranous and indiscernible. Remarks. Specimens from the Pinaleno Mountains represent the most extreme southwestern distribution of this species and are isolated from the more contiguous mountain ranges to the north and east. Hoffmeister (1956) also considered the vole population in the Pinalenos as a subspecies (M. longicaudus leucophaeus) distinct from other Arizona and New Mexico species of M. longicaudus. Evolution of this flea subspecies may follow that of its host; however, definitive studies (DNA or karyotype) have not been conducted to validate Hoffmeister s subspecific designation in support of this proposal. Although we place the Pinaleno population with H. d. obliqua, note that the oblique apex of DA9 is more variable than material from the Mogollon, Tularosa, Mimbres, San Mateo, and Manzano Mountains of New Mexico, and the mountains of Nuevo León, Mexico where this feature is constant. In general, the two arms of DA9 of all members of this genus are fused from base to apex, forming a trough between the two distal arms. There are usually six or seven pairs of dark spiniform setae along the ventral margin, the ventral two pairs separated typically by more space than is found in that of H. d. truncata. This space has one or two short spiniform setae in 76 of the 78 males examined. The two specimens that lack this spiniform are considered intergrades and they occur in the Pinaleno (Figures 3F-G) and San Mateo Mountains. Conversely, seven of 42 males of H. d. truncata also possessed this spiniform setal pattern (interestingly in the zone of intergradation of specimens just north and south of New Mexico Interstate Highway 40 east of the Rio Grande in Bernalillo County). One of these also occurred in the northern portion of the White Mountains west of the Blue Range Primitive Area, five in the Jemez Mountains, and one in the Sandia Mountains (Figure 3J, paratype). The zone of intergradation of H. d. obliqua and H. d. truncata appears to occur in a region just north and south of U.S. Interstate 40, and to the southwest. Habitats in New Mexico regions east of 105 W latitude are too dry to support populations of either H. dippiei ssp. or H. occidentalis ssp. Several records were provisionally reported in New Mexico as H. d. truncata by Holland (1957). Mogollon Mountains was indicated on one such slide of a female that was examined [referenced in Holland (1957) as Catron Co., 7900, 2 males, 1 female] and is within the distribution of the new subspecies. His records listed from San Miguel County (1 male, 2 females examined) and those 25 miles E Albuquerque (Bernalillo County, 1 male, 2 females examined) belong to H. d. truncata. The latter three specimens are labeled as paratypes but are not listed as paratypes in Holland s (1957) description of H. d. truncata. The male recorded from Pinos Altos, Grant County, NM, was not examined, but surely belongs to the new subspecies, since it occurs in the southern part of the Mogollon Volcanic Plateau (Ungnade 1972). Only three (1 male, 2 females) specimens of H. d. obliqua

6 256 Journal of Vector Ecology December 2005 were collected from trapped hosts, i.e., three of seven M. longicaudus (Pinaleno populations considered the subspecies leucophaeus by early workers) in the Pinaleno Mountains during spring and fall. The yield of Hystrichopsylla on P. maniculatus was negative. The infestation of voles but not mice may be attributed to higher populations of fleas in vole nests than those in mouse nests. Voles constructed their nests on and in moist soil, but mice preferred drier sites whose microhabitats were unsuitable for development of this flea. Ford et al. (2004) cite records of Hystrichopsylla dippiei from a dozen hosts in four New Mexico counties (Bernalillo, Sandoval, Santa Fe, and Socorro). Based on their distribution, those from the latter county are likely H. d. obliqua, those from Sandoval and Santa Fe H. d. truncata, and those from Bernalillo could belong to either subspecies. Tipton and Méndez (1968) discuss 36 (9 males, 27 females) specimens of Hystrichopsylla from Cerro Potosi, Nuevo León, Mexico, indicating that they were to be described by Traub and Barrera. This description was never published. Seven of these specimens (2 males, 5 females) from the Traub collection (CMNH) were examined and are conspecific with this new subspecies. A single female (not examined) with the same data as one of the CMNH specimens is listed by Ayala- Barajas et al. (1988) as Hystrichopsylla dippiei Rothschild, We were unable to locate the other 28 specimens. The presence of H. d. obliqua so far south in Mexico is puzzling, since there are no linking mountain ranges for 1,200 km that have sufficient elevation necessary for the ecology of this flea. Perhaps this species will be discovered in the Sierra Madre Occidental Range to the west, which provides a geographical link between the Sierra Madre Oriental Range and the southern montane regions of New Mexico. Additional collection of nests in alpine habitats of the Sierra Madre Occidental is needed to understand the association of Mexican and United States populations of this new subspecies. Note of clarification: Tipton and Méndez (1968) inadvertently indicated that Cerro Potosi was in the Sierra Madre Occidental Range in the first sentence of their introduction instead of the Sierra Madre Oriental Range. This is pointed out to preclude confusion for future workers. Holland (1957) suggested that H. kris was probably conspecific with H. orophila based on the premise that the spiracle of tergum VIII might be an anomaly. The authors examined a single female collected from Microtus sp. between Mexico City and Puebla, 3,140 m, leg. M.D. Tuttle (CMNH) and propose to dispel Holland s observation. The spiracle of this enormous flea (7 mm) did not reach the margin of tergum VIII and its position and shape was indistinguishable from that of the female holotype illustrated by Traub and Johnson (1952). Although the female of H. orophila has not been described, we examined a pair of Hystrichopsylla (both with six genal ctenidia) from the same host (Microtus sp.), 26 km SSW of Toluca, State of Mexico, leg. A.D. Stock and R. Traub (CMNH). The male is clearly H. orophila. The associated female is likely the same taxon, but a description of the single female would be premature. Future collections of the nests of Microtine and Sigmodontine rodents in subalpine habitats are needed to discover the male of H. kris and additional females of H. orophila to enable their description. Etymology: As with the sister taxon, H. d. truncata, the subspecific name is given for the characteristic shape of the apex of the st. IX, which is distinctly oblique as opposed to truncate. Figure 1. Map illustrating distribution of Hystrichopsylla ssp. in Arizona and New Mexico [AP=Apache National Forest (NF), CB=Cibola NF, CON=Coconino NF, COR=Coronado NF, GI=Gila NF, LI=Lincoln NF, SF=Santa Fe NF, and TON=Tonto NF].

7 Vol. 30, no. 2 Journal of Vector Ecology 257 Hystrichopsylla dippiei truncata Holland, 1957 Figure 1, Figures 3H-L, Table 1 Type Material. -Hystrichopsylla dippiei truncata Holland, The Canadian Entomologist, 84: , Figure 23. Type Locality. Canada, British Columbia, Okanagan Landing, ex Peromyscus maniculatus artemisiae [= P. maniculatus], 15 September 1950, J.D. Gregson (holotype No. 6547, Canadian National Collection of Insects, Ottawa). Hystrichopsylla dippiei truncata (see Lewis and Lewis 1994 for listing of synonymies) Material Examined: Arizona: Apache County. White Mountains: 5.5 km SSW Greer, NW Winn Campground, 2,737 m, ( "N "W), M. montanus, 28 September 1989, N. Wilson, 1 male; 2.2 km SE Big Lake, Big Lake Knoll near lookout on summit, 2,860 m, ( "N "W), T. hudsonicus nest, 13 September 1986, G.E. Haas (3), 1 male; 5.5 km SSW Greer, NW Winn Campground, 2,835 m, ( "N "W), T. hudsonicus nest, 18 August 1987, G.E. Haas (3), 1 male; 5.5 km SSW Greer, Figure 2. A-C. Hystrichopsylla d. obliqua n. sp. A. Head, thorax and abdomen (holotype). B. Head, thorax and abdomen (allotype). C. Apex of aedeagus (paratype, Mogollon Mts., NM) (ae.p., aedeagal pouch; d.ar., dorsal armature; F.sc., Ford s sclerite; l.l., lateral lobe; m.d.l., median dorsal lobe; and s.i.t., sclerotized inner tube). 0.2 km NW Winn Campground, W side of Creek from Sam Hale Reservoir, 2,737 m, ( "N "W), N. mexicana nest, 25 September 1989, G.E. Haas (3), 1 female; 6 km SSW Greer, 0.4 km S Winn Campground, 2,853 m ( "N "W), T. hudsonicus nest, 27 September 1991, G.E. Haas (3), 2 males, 2 females; Escudilla Mt., 8.5 km ENE Alpine, Toolbox Draw near trail head #308, 2,941 m, ( "N W), T. hudsonicus nest, 19 August 1993, G.E. Haas (3), 1 male; Lee Valley near NE shore Lee Valley Reservoir, 2,872 m, ( "N "W), M. longicaudus nest, 18 August 1987, G.E. Haas (3), 2 males, 4 females; 5.7 km SSW Greer, S entrance to Winn Campground, 2,842 m, ( "N "W), M. montanus nest, 26 September 1989, G.E. Haas (2), 1 male; 5.8 km SSW Greer, S Winn Campground, E Forest Road 554, 2,853 m, ( "N "W), M. montanus nest, 28 September 1989, G.E. Haas (2), 2 males; Alpine Divide (pass), 5.6 km NNW Alpine, 0.5 km NW Alpine Divide Campground, W highways 180/191, 2,595 m, ( "N "W), M. longicaudus nest, 25 September 1993, G.E. Haas (3), 1 male (GEH) Cochise County. Chiricahua Mountains: 0.8 km E Cima Ranger Station, 2,590 m, (~31 50 N W), P. maniculatus or Peromyscus truei (Shufeldt), 30 July 1960, R.W. Thorington, 1 male, 1 female; Rustlers Park, (31 54 N W), Peromyscus sp., 6 September 1960, H. Howden, 1 female (CMNH); 5.5 km WSW Paradise, rock slide S side of Barfoot Peak, 2,560 m, ( "N "W), Peromyscus boylii (Baird) (2 specimens), October 1994, G.E. Haas (3), 1 male, 2 females; 6 km WSW Paradise, rock slide S side of Barfoot Peak, 2,525 m, ( "N "W), P. maniculatus, 25 November 1989, G.E. Haas (3), 1 female (GEH); Portal (Onion Gap to Rustlers Park), 2,323-2,576 m, ( "N "W to N "W), P. boylii, August 1952, J. Beer, 1 male (UMINN). Coconino County. Kaibab Plateau: Marble Point, 2,725 m, ( "N "W), M. longicaudus, 3 September 1998, J.R. Kucera, 1 male, 1 female; Dog Lake, 2,688 m, ( "N "W), P. maniculatus, 5 June 1992, J.R. Kucera, 1 female; VT Lake, 2,686 m, ( "N "W), T. hudsonicus nest, 26 May 2002, J.R. Kucera, 1 male; along road between Watts and Quaking Aspen Springs, 2,380 m, (~ "N "W), M. longicaudus nest, 24 September 2004, J.R. Kucera, 1 female; Quaking Aspen Springs, 2,370 m, (~ "N "W), M. longicaudus nest (3 adult voles present), 24 September 2004, J.R. Kucera, 1 male; same except pool of two nests, 25 September 2004, J.R. Kucera, 1 male, 1 female; same except rodent nest under log, 1 male (JRK); 24 km SSE Jacob Lake, VT Lake, E side highway 67, 2,646 m, ( "N "W), M. longicaudus nests (2), 4 September 1991, G.E. Haas (3), 2 male, 2 females; De Motte Park (in forest), 2,740 m, ( "N "W), T. hudsonicus nest, 19 August 1986, G.E. Haas (3), 1 female (GEH). Greenlee County. Blue Range: 0.6s km SSW Hannagan Meadow, Hannagan Meadow Campground, 2,788 m, ( "N "W), M. longicaudus nest, 8 May 1981, G.E. Haas (3), 1 male; same data except 2,784 m, 7.2 km SSW of Hannagan Meadow, NW KP Cienega, NW tributary of KP

8 258 Journal of Vector Ecology Figure 3. A-G. Hystrichopsylla d. obliqua n. sp. A. Distal arm of ninth sternum and eighth sternum. B. Distal arm of ninth sternum, basimere and telomere (paratype, San Mateo Mts., NM). C. Terminal segments of female (allotype). DG. Distal arm of ninth sternum (paratypes). D. Manzano Mts., NM. E. Mogollon Mts., NM. F-G. Pinaleno Mts., AZ. H-L. Hystrichopsylla d. truncata, distal arm of ninth sternum. H. Chiricahua Mts., AZ. I. White Mts., AZ. J. Sandia Mts., NM. K. Henry Mts., UT. L. Kaibab Plateau, AZ. Creek, 2,731 m, ( "N "W), M. longicaudus nest, 19 August 1987, G.E. Haas (3), 2 males, 1 female; 2 km SSW Hannagan Meadow, NW KP Cienega Campground, 2,755 m, (33 34'40"N "W), M. longicaudus nest, 25 May 1990, G.E. Haas (3), 2 males; 7.6 km SSW Hannagan Meadow near site # 3 at KP Cienega Campground, 2,739 m, ( "N "W), M. longicaudus nest, 11 September 1997, G.E. Haas (3), 2 males, 2 females (GEH). New Mexico: Bernalillo County. Sandia Mountains: 40 km E Albuquerque, P. maniculatus, 22 May 1949, C.C. Hoff and H.H. Lewis, 1 male (paratype), same data except Eutamias quadrivittatus = Tamias quadrivittatus (Say), 1 female (paratype), same data except Peromyscus nasutus (J.A. Allen), 23 April 1949, H.H. Lewis, 1 female (paratype) (CNC); 2.5 km ENE Sandia Crest, Ninemile Picnic Area, 2,810 m, ( "N "W), P. maniculatus nest, 10 August 1991, G.E. Haas (3), 1 female; same data except 12 September 1994, 2 males, 1 female (GEH). Los Alamos County. Jemez December 2005 Mountains: south cliff of Boulder Mt., 2,316 m, ( "N "W), M. longicaudus, 23 January 1970, G.E. Haas (3), 1 female; same data except P. truei (n=3), January 1970, 2 males, 1 female; Limber Pine Line, W Boulder Mt., 2,347 m, ( "N "W), P. truei (n=2), January 1970, G.E. Haas (3), 2 males, 1 female; same data except 16 May 1970, 1 female; overlook at highway 4 and Water Canyon, 2,426 m, (35 50 N "W), P. truei (n=2), 30 November 1969, G.E. Haas (3), 1 male, 3 females; Los Alamos Canyon, north side of Omega Road, 2,164 m, ( "N "W), P. truei, 26 April 1970, G.E. Haas (3), 1 male; and Pajarito Mt., north side ski slope, 3,016 m, ( "N "W), T. hudsonicus nest, 28 July 1970, G.E. Haas (1), 1 female (GEH). Rio Arriba County. San Pedro Mountains: 48.3 km E Cuba, (~36 03 N W), M. pennsylvanicus, 20 September 1951, 1 male (CNC). Sandoval County. Jemez Mountains: N of junction highway 4 and St. Peters Dome Road, Forest Road 142, 2,737 m, ( "N "W), M. montanus, 16 June 1970, G.E. Haas (3), 1 female; same data except 21 July 1970, 1 male; W side Frijoles Canyon along St. Peters Dome Road, Forest Road 142 in rock fill, 2,699 m, ( "N "W), P. maniculatus, 13 May 1970, G.E. Haas (3), 1 male; SE junction highway 4 and St. Peters Dome Road, Forest Road 142, 2,725 m, ( "N "W), P. maniculatus, 7 May 1970, G.E. Haas (3), 1 female; Rockslide, Sierra de los Valles at SE corner of Valle Grande, 2,682 m, ( "N "W), Tamias minimus Bachman, 18 September 1970, G.E. Haas (3), 1 male, 1 female (GEH); M. montanus, 3, August 1971, G.E. Haas (3), 1 male, 2 females; same data except E. quadrivittatus = T. quadrivitatus, 4 August 1971, 1 male, 1 female; and same data except P. maniculatus, 5 August 1971, 1 male, 1 female (CNC). San Miguel County. Sangre de Cristo Mountains: 27 km N Pecos, 2,440 m, (~35 49 N W), Spermophilus lateralis (Say), 28 July 1950, H. Stark, 1 male, 1 female; Holy Ghost Canyon, (~35 46 N W), S. lateralis, 17 June 1953, H.B. Morlan, 1 female (CNC); 4.5 km SW Cowles, Holy Ghost Canyon, 2,542 m, ( "N "W), M. longicaudus nest, 26 August 1993, G.E. Haas (1), 1 female; 4.5 km SW Cowles, Holy Ghost Canyon, 2,524 m, ( "N "W), M. longicaudus nest, 26 August 1993, G.E. Haas (1), 1 female; 10.5 km NNW Pecos, Dalton Canyon, 2,262 m, ( "N "W), T. hudsonicus nest, 27 August 1993, G.E. Haas (3), 2 males (GEH); Grass Mt., Winsor Ranch, 2,743 m, (~35 49 N W), S. lateralis, 9 August 1961, 1 male (USNM). Santa Fe County. Sangre de Cristo Mountains: Ski Basin, (~35 48 N W), M. longicaudus, 5 November 1952, H.B. Morlan, 1 male; same data except 6 August 1953, 1 male; Pacheco Canyon, (~35 48 N W), E. quadrivittatus = T. quadrivittatus, 30 August 1951, H.B. Morlan, 2 females; same data except Neotoma cinerea (Ord), 1 female; Hyde Park, (~35 45 N W), Neotoma sp., 3 April 1951, H.B. Morlan, 1 female (CNC). Utah. Garfield County. Henry Mountains: 2,287 m (~38 07 N W), mouse nest, 20 July 1968, J.E.H. Martin, 1 male, 1 female; and 39 km S Hanksville, 2,287 m, (~38 07 N W), Peromyscus sp.,

9 Vol. 30, no. 2 Journal of Vector Ecology 259 Table 1. Number of male and female Hystrichopsylla dippiei subspecies found in a specified number of nests of host mammals in Arizona and New Mexico. Microtus Neotoma Tamiasciurus TOTAL mexicanus montanus longicaudus mexicana hudsonicus Hystrichopsylla dippiei obliqua 1N/1 male, 1 female* 23N/51 males, 109 females 9N/52 males, 68 females 9N/38 males, 57 females 42N/142 males, 235 females Hystrichopsylla dippiei truncata 4N/5 males, 11 females 15N/16 males, 25 females 1N/1 male 7N/6 males,6 females 27N/27 males, 43 females TOTAL 1N/1 male, 1 female 4N/5 males, 11 females 38N/67 males, 134 females 10N/52 males, 69 females 16N/44 males, 63 females 69N/169 males, 278 fermales *N=number of rodent nests examined/number of male fleas, number of female fleas.

10 260 Journal of Vector Ecology December July 1968, J.E.H. Martin, 10 males, 8 females (CNC). San Juan County. Abajo Mountains: W Dalton Springs Campground, N North Creek Road, 2,316 m, (37 54 N W), T. hudsonicus nest, 22 September 1996, G.E. Haas (3), 1 male, 1 female; La Sal Mountains: 20.5 km N La Sal, 0.12 km S Oowah Lake, 2,682 m, ( "N "W), T. hudsonicus nest, 15 June 1991, G.E. Haas and J.R. Kucera (3), 1 male, 1 female. (GEH). Remarks: Hystrichopsylla d. truncata is broadly distributed in the mountainous regions west of the great plains and east of the Cascade and Sierra Nevada ranges from British Columbia, Canada to the northern half of Arizona and New Mexico. This subspecies is replaced by H. d. obliqua to the south and H. d. neotomae to the extreme west (California). It is indiscriminate in its host selection, developing in the moist nests of chipmunks, mice, voles, red squirrels, and occasionally wood rats. Like others belonging to the H. dippiei complex, it is primarily a nest flea, collected only infrequently in the fur of host animals. Additional specimens of H. d. truncata were examined from Garfield, Grand, and San Juan Counties, UT for comparison of Arizona specimens. Specimens from each of these isolated Utah mountain ranges were conspecific with H. d. truncata from the northern regions of Arizona and New Mexico; however, it should be noted that the DA9 of all specimens from the Kaibab Plateau were markedly much broader than other typical specimens of H. d. truncata (or H. d. obliqua) (Figure 3L). Populations from the Kaibab Plateau deserve additional collecting and assessment. The occurrence of H. d. truncata in Rio Arriba County, NM is a new record for that county. Only three males exist from the Chiricahua Mountains. Although they are separated from the northern population of H. d. truncata by the isolated Pinaleno population of H. d. obliqua, they are rightfully assigned to H. d. truncata. Two such specimens reported as H. dippiei by Beer et al. (1959) were collected from a Douglas fir-yellow pine association between Onion Gap and Rustlers Park. Lewis and Lewis (1994) included this male in their synonymies as H. dippiei dippiei. All three of these males possess flattened scales on the dorsal angle of the DA9. The DA9 is also very truncate and arched anteriorly, forming a concavity on the dorsal margin. Two of the three possess a small spiniform between the proximal and penultimate pair of spiniforms on the DA9, a characteristic of H. d. obliqua. This might be expected in any population of H. d. truncata that is geographically associated with H. d. obliqua. The sex ratio (males:females) of H. d. truncata recovered from nests was 0.7:1.0 (n=85) compared to H. d. obliqua, which was 0.66:1.0 (n=266). The sex ratio for the combined total number of Hystrichopsylla d. ssp. was 0.67:1.0 (n=351). Marshall (1981) proposed that at the time of emergence of adult fleas, the sex ratio is usually about equal (based on sample sizes of 100 or more). He concluded that male fleas are shorter-lived and eventually females predominate on hosts and in their nests. Immediate extraction of fleas (dead and alive) from nests and subsequent tabulation of all reared fleas would effectively eliminate this differential. Therefore, our findings would suggest that H. dippiei species produce more females than males as a biological entity inherent in the species studied. The disparity between the number of fleas extracted from nests illustrated in Table 1 and those used in calculating sex ratios can be explained by two criteria: 1) fleas from all nests were not used to determine sex ratios. Nests that were considered dry or medium dry were not included, although a few fleas may have been present in such nests. An assumption was made that only a moist nest thriving with numerous fleas would reflect a true sex ratio, hence, only those nests were selected; and 2) only nests were included in Table 1 for which the identity of each flea positive nest could be accurately associated with a specific host species (some were uncertain). Hystrichopsylla occidentalis sylvaticus Campos and Stark, 1979 Figure 1 Type Material: Hystrichopsylla occidentalis sylvaticus, Campos and Stark, 1979, J. Med. Entomol. 15: 442, Figures 1-15 (USNM , primary type missing). Type Locality: Holotype male, Foothills Research Campus, 2.5 km W Ft. Collins, CO, 1,580 m, ex Peromyscus difficilis (J.A. Allen), 24 October 1969, E.G. Campos. Hystrichopsylla occidentalis sylvaticus (see Lewis and Lewis 1994 for listing of synonymies) Lewis and Lewis (1994) discussed the distribution of the H. occidentalis complex. The H. o. linsdalei reported by Fagerlund et al. (2001) from Colfax County, NM is certainly a misidentification and probably represents H. o. sylvaticus. Unfortunately, the specimen was apparently used for plague analysis (proved positive for Yersinia pestis) and was destroyed in the procedure. This dubious record is not illustrated in Figure 1. Hystrichopsylla o. sylvaticus is mainly allopatric with H. d. ssp. in Arizona and New Mexico (Figure 1). This might be attributed to the drier habitats of the Rocky Mountain Montane conifer forest where only a few specimens have been collected by Haas and Kucera (unpublished data) and four specimens that were reported by Campos and Stark (1979) near Williams (Coconino County), and Payson (Gila County), AZ. We examined two females from Colorado (label data = Antonito, Conejos County, CO A.P.#8049A, [ex:] Says Gr. Sq., ), which is likely H. o. sylvaticus based on seven genal ctenidia on each side of the head of both specimens. These were located just north of the New Mexico border near Fagerland s record in Colfax County (exact location unknown). Nest Requirements of Hystrichopsylla dippiei ssp. The complex of Hystrichopsylla species inhabiting the southwestern United States occupy extremely different ecological niches. Hystrichopsylla d. neotomae and H. o. linsdalei are restricted to California, each occurring at lower elevations, whereas H. d. truncata, H. d. obliqua, and H. o. sylvaticus are found at higher elevations, usually in subalpine environments of conifer forests. Except for personal communication from H.J. Egoscue cited by Campos and Stark (1979) regarding H. o. sylvaticus, previous knowledge of the